1. Field of the Invention
This invention relates to an air-permeable shoe.
2. Description of Background Art
Hithertofore, an air-permeable shoe sole having an open-cell rubber foam inset therein has been proposed as set forth in Japanese Patent Publication No. 21285-1963. This sole incorporates a side surface of rubber foam which is exposed on a side surface of the sole. Because an open-cell rubber foam is combined with an air-permeable member of structure present in this shoe, air within the shoe can be discharged from the inside of the shoe to a side surface of the sole. However, in a conventional type of air-permeable shoe, a disadvantage occurs when the humidity within the shoe rises due to wearing the shoe for a long period of time or due to high humidity in the ambient atmosphere such as occurs on a rainy day. Water, which forms from moisture and in turn condenses, clogs up the open cells of the open-cell rubber foam to cause the air permeability thereof to become considerably reduced.
In addition, open-cell rubber foam is weak in mechanical properties such as tension strength, internal tearing resistance and bending resistance characteristics. Thus, open-cell rubber foam presents a durability problem when used as a component material of a sole.